Vomiting-related ER visits increased 29% in Colorado after cannabis legalization
Vomiting-related emergency department visits in Colorado rose from 119,312 in 2013 to 153,699 in 2018, with additional recreational dispensaries associated with increased visit rates.
Quick Facts
What This Study Found
Vomiting-related ED visits increased 29% over the study period. Each additional recreational dispensary was associated with a 3% increase in vomiting-related visits (IRR 1.03). However, counties with high baseline medical dispensary exposure experienced smaller increases than counties with no prior dispensaries (IRR 0.97).
Key Numbers
Total patients: 820,778. Visits 2013: 119,312. Visits 2018: 153,699. Increase: 29%. Recreational dispensary IRR: 1.03. Counties with prior medical dispensaries grew 5.8% slower. Female: 62%. Ages 0-18: 25%.
How They Did This
Cross-sectional analysis of 820,778 patients with vomiting-related ED claims reported to the Colorado Hospital Association from January 2013 to December 2018, examining the relationship between dispensary density and visit rates by county.
Why This Research Matters
This large-scale analysis provides population-level evidence connecting cannabis market expansion to increased vomiting-related healthcare utilization, likely reflecting cannabinoid hyperemesis syndrome.
The Bigger Picture
The finding that counties with established medical dispensaries saw slower increases suggests a possible habituation or education effect in markets with longer cannabis exposure.
What This Study Doesn't Tell Us
Cannot confirm cannabis as the cause of vomiting. ED claims data may include multiple visits by the same patient. No direct measure of cannabis use among patients presenting with vomiting.
Questions This Raises
- ?Is the slower growth in counties with established dispensaries due to clinician awareness, consumer education, or demographic differences?
- ?What proportion of these vomiting visits are actually CHS?
Trust & Context
- Key Stat:
- 29% increase in vomiting-related ER visits over 5 years post-legalization
- Evidence Grade:
- Large population-level dataset with county-level dispensary data, but cannot directly link individual vomiting cases to cannabis use.
- Study Age:
- Published in 2021 using Colorado data from 2013-2018.
- Original Title:
- Changes in Emergency Department Encounters for Vomiting After Cannabis Legalization in Colorado.
- Published In:
- JAMA network open, 4(9), e2125063 (2021)
- Authors:
- Wang, George Sam(15), Buttorff, Christine(4), Wilks, Asa(4), Schwam, Daniel, Tung, Gregory, Pacula, Rosalie Liccardo
- Database ID:
- RTHC-03601
Evidence Hierarchy
A snapshot of a population at one point in time.
What do these levels mean? →Frequently Asked Questions
Did cannabis legalization increase ER visits for vomiting?
Vomiting-related ER visits rose 29% in Colorado from 2013 to 2018, and each additional recreational dispensary was associated with a 3% increase in visit rates.
Did areas with existing medical marijuana dispensaries see the same increase?
No. Counties that already had medical dispensaries before recreational legalization experienced 5.8% slower growth in vomiting-related visits than counties with none.
Read More on RethinkTHC
Cite This Study
https://rethinkthc.com/research/RTHC-03601APA
Wang, George Sam; Buttorff, Christine; Wilks, Asa; Schwam, Daniel; Tung, Gregory; Pacula, Rosalie Liccardo. (2021). Changes in Emergency Department Encounters for Vomiting After Cannabis Legalization in Colorado.. JAMA network open, 4(9), e2125063. https://doi.org/10.1001/jamanetworkopen.2021.25063
MLA
Wang, George Sam, et al. "Changes in Emergency Department Encounters for Vomiting After Cannabis Legalization in Colorado.." JAMA network open, 2021. https://doi.org/10.1001/jamanetworkopen.2021.25063
RethinkTHC
RethinkTHC Research Database. "Changes in Emergency Department Encounters for Vomiting Afte..." RTHC-03601. Retrieved from https://rethinkthc.com/research/wang-2021-changes-in-emergency-department
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkTHC research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.